Emily and Mastodon, what do you think would happen if you told your spouses? Would they judge you? Get angry? Be derisive or otherwise disrespectful about something that is important to you? Be intrusive or disrespectful of your privacy?
Only you know what is right for you of course. But I wonder if this isn't a missed opportunity for greater intimacy in your relationship. Not that you owe them any particular information but if your relationship is generally safe and loving (big if--I know!) it might be nice to know each other better.